Expression of hypoxia inducible factor-1a and vascular endothelial growth factor in retina during rat embryon development / 中华实验眼科杂志

ABSTRACT

Background Research determined that hypoxia inducible factor-1(HIF-1)is associated with the hypoxia response in normal organ,and it plays an important role during the embryon development.It is also proved that the expression of vascular endothelial growth factor(VEGF)is upregulated in embryon retina.But,whether the action of HIF-1 and VEGF is correlated is unclear. Objective The aim of this study was to investigate the dynamic change of expression of HIF-1α and VEGF in retina during embryonic development and explore the role of HIF-1α and VEGF along with retinal evolvement.Methods The different embryon ages of SD rats were obtained from 30 clean pregnant SD rats by cesarean surgery.The retinas were isolated from embryon 10一day,12一day,14-day,16-day and 20-day rats respectively.The expressions of HIF-1 α and VEGF protein in retina were semi-quantitatively and qualitatively determined by immunochemistry,and the expressions of HIF-l α and VEGF mRNA in retina with different-embryon-phase and adult rats were detected by RT-PCR. Results The hishly level of expression of HIF-1 α and VEGF protein were found in the cellular nuclei and cytoplasm of retina in embryon 10一and 12-day rats.With the increase of embryon age.the expression of HIF-1α and VEGF protein in retina lowed(F=56.70,P<0.01；F=60.78.P<0.01).Compared with the adult rats,the expressions of HIF-1α and VEGF protein in retina were higher from embryon 0-day through 20-day rats(all P<0.01).The significantly positive correlation was found in the expression level between HIF-1α and VEGF protein throughout the experimental duration(r=0.96,P=0.00).Followed the same pattern,the expression levels of HIF-1α and VEGF mRNA in retinas were also enhanced in the embryon 10- and 12-day rats.Identically,a gradually weakened trend was seen in the expressions of HIF-1 α and VEGF mRNA in retinas as the increase of gestational age of rats(F=68.84,P<0.01；F=96.49,P<0.01),and the exDressions of HIF-1 α and VEGF mRNA decreased in the adult rats compared with different embryon-phase rats,showing a statistically significant difference between them(all P<0.01). Conclusion The expressions of HIF-1 αand VEGF in retina appear a dynamic alteration from hish to low during the embryonic development of rat retina,indicating that HIF-1α/VEGF pathway might participate in the process of embryo development of rat retina.